Placental mesenchymal dysplasia

Placental mesenchymal dysplasia (PMD) is a rare, benign condition that is characterised by enlargement of the placenta with multiple bunch of grape-like vesicles that can resemble a molar pregnancy by ultrasound and gross pathologic examination.

Radiographic features

Ultrasound

The placenta is thickened with multiple cystic or hypoechoic areas. Doppler findings are variable. There are many documented cases of no vascularity within the lesion and further development of vascularity within. These changes could be due to progressive dilatation of chorionic arteries and veins that becomes aneurysmal.

MRI

One study showed that MRI could help differentiate between complete hydatidiform mole with coexistent fetus (CHMTF) by demonstrating PMD within the placenta and CHMTF within an extra fetal sac 4.

Treatment and prognosis

The outcome of the fetus is variable ranging from a completely normal fetus to an increased risk of IUGR or fetal demise.